<template>
    <div>message的值：{{ message }}</div>
    <div>obj.message的值：{{ obj.message }}</div>
</template>

<script setup>
       import { reactive, toRefs } from 'vue'
       const obj = reactive ({ message:'盛年不重来，一日难再晨'})
       let { message } = toRefs(obj)
       setTimeout(() => {
        message.value = '即使当勉励，岁月不待人'
       }, 2000)
</script>